Custom board nfc antenna configuration

[Lewy2552]

I am currently in the process of creating a custom pcb board that uses the nrf52840 processor in order to send bluetooth packets out from my board. I have successfully been able to get my board to run my code and send consistent bluetooth packets from its antenna.

The issue i am running into is that I am not able to recieve nfc messages from my on board antenna. When I am using my development kit board, I am able to recieve the message from my nfc antenna. How can I debug into this issue and see what is going wrong with my custom antenna? How does the url go from the processor registers to the antenna properly. (I noticed there is a dedicated line from the processor to the antenna, but i dont have to call to that pin when im encoding the tag within my code)

[helsing]

Hi Andrew,

Have you tuned the antenna after connecting it to your custom board? Have you had a look at nWP026 - nRF52832 NFC Antenna Tuning ?

Has anyone at Nordic reviewed the schematic and layout of your custom board? We offer a review of the Nordic related part of the board as a free service. We can make the ticket private if you would like to upload files.

Which SDK version are you using?

[Lewy2552]

Hey,

Sorry for the long delay on this. I had to put this project off for a little while. We followed the white papers and tried to match the exact tuning/hardware of the antenna. We are still not able to get any message from the antenna. Is there any ideas on how to move on from the white paper?

[Lewy2552]

Another question that I want to ask is if there is a difference between the development kit 52840 processor and the mdbt50q processors. We are trying to eliminate all the possibilities that are causing the antenna not to work on the board. thanks!

[Susheel Nuguru]

Hi, It is a long weekend for many in Norway and many are away today. You will most likely get a response on Monday.
Thanks you for your patience so far.

[Lewy2552]

All good! I found the issue was related to the NFCPINS in the UICR was set to some crazy integer (something like 48527). We created a piece of code that overwrites that register value and the nfc works now!